#language-design

1 item tagged "language-design".

Posts

• Opaque Types in Swift: Understanding the `some` Keyword

  Posted on:February 15, 2025

  · 6 min read

  `some` doesn't just hide a type behind a protocol — it preserves the underlying concrete type identity through the compiler. Here's what that means for performance and why `any` exists alongside it.

  swiftioslanguage-design